The ratio of the corresponding side lengths is 10: 710: 7. what is the ratio of the areas?

Pls the last one and it has to be like number 6

A50-foot ladder is leaning against a vertical wall. if the base of the ladder is 45 feet from the base of the wall, find the angle the bottling of the ladder makes with the ground.

Which image (a’ b’ c’ d’) of abcd cannot he produced using only reflections ?